Classifications

• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
  • B01J20/00—Solid sorbent compositions or filter aid compositions; Sorbents for chromatography; Processes for preparing, regenerating or reactivating thereof
  • B01J20/02—Solid sorbent compositions or filter aid compositions; Sorbents for chromatography; Processes for preparing, regenerating or reactivating thereof comprising inorganic material
  • B01J20/10—Solid sorbent compositions or filter aid compositions; Sorbents for chromatography; Processes for preparing, regenerating or reactivating thereof comprising inorganic material comprising silica or silicate
  • B01J20/16—Alumino-silicates
  • B01J20/18—Synthetic zeolitic molecular sieves
  • B01J20/186—Chemical treatments in view of modifying the properties of the sieve, e.g. increasing the stability or the activity, also decreasing the activity
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
  • B01J20/00—Solid sorbent compositions or filter aid compositions; Sorbents for chromatography; Processes for preparing, regenerating or reactivating thereof
  • B01J20/02—Solid sorbent compositions or filter aid compositions; Sorbents for chromatography; Processes for preparing, regenerating or reactivating thereof comprising inorganic material
  • B01J20/10—Solid sorbent compositions or filter aid compositions; Sorbents for chromatography; Processes for preparing, regenerating or reactivating thereof comprising inorganic material comprising silica or silicate
  • B01J20/16—Alumino-silicates
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
  • B01J2229/00—Aspects of molecular sieve catalysts not covered by B01J29/00
  • B01J2229/10—After treatment, characterised by the effect to be obtained
  • B01J2229/12—After treatment, characterised by the effect to be obtained to alter the outside of the crystallites, e.g. selectivation
  • B01J2229/126—After treatment, characterised by the effect to be obtained to alter the outside of the crystallites, e.g. selectivation in order to reduce the pore-mouth size
• • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
  • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
  • Y10S—TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
  • Y10S95/00—Gas separation: processes
  • Y10S95/90—Solid sorbent
  • Y10S95/902—Molecular sieve
• • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
  • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
  • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
  • Y10T428/00—Stock material or miscellaneous articles
  • Y10T428/29—Coated or structually defined flake, particle, cell, strand, strand portion, rod, filament, macroscopic fiber or mass thereof
  • Y10T428/2982—Particulate matter [e.g., sphere, flake, etc.]
  • Y10T428/2991—Coated
  • Y10T428/2993—Silicic or refractory material containing [e.g., tungsten oxide, glass, cement, etc.]
  • Y10T428/2995—Silane, siloxane or silicone coating

Definitions

• This invention relates to a method for pore size modification in such a way that specific molecular sieving effects can be obtained by controlled pore size reduction, and that encapsulation of compounds, elements or ions can be performed by pore closure.
• porous materials such as zeolites can adsorb gases and other materials, and that they can take in ions by ion exchange, provided that the pores of the substrate are large enough.
• a purely physical sorption or ion exchange is a equilibrium process depending on concentration, pressure, temperature etc. It is therefore essentially reversible and not suitable for immobilising ions or molecules in a stable manner in a solid matrix.
• the European Pat. No. 80103117.0 (Penzhorn) describes a similar method for encapsulating gas molecules in zeolites under high pressures and high temperatures.
• the encapsulation is based on a thermal vitrification of the zeolite in the presence of a pressurised gas. Under this pressure, and at higher temperature, the zeolite transforms into amorphous stable material, containing the enclosed gas molecules.
• the European Pat. No. 81201137.7 describes the possibility to encapsulate gas molecules and other molecules by closing or narrowing the zeolite pores after sorption under normal conditions of temperature and pressure.
• the pore size reduction is obtained by a structural modification process, based on chemisorption of a modifier such as SiH 4 , B 2 H 6 , etc. on structural hydroxyl groups, followed by further reaction with O 2 , H 2 O, CH 3 OH, etc.
• a mordenite sample was degassed (dehydrated) in a vacuum at 450° C. and 1.95 meq NH 4 + /g dry material was then adsorbed.
• the following treatments were applied: boranation at 20° C., heating at 150° C., boranation at 150° C., heating at 400° C., oxidation with H 2 O and dehydration at 400° C. After each step sorption capacities were measured. The results, tabulated below, indicate that a small boranation results in a dramatic exclusion of N 2 at -196° C.
• boranation reactions proceed intensively, and a further strong pore size reduction is observed. After oxidation, adsorption appears to be limited to the external surface and the zeolite pores are closed completely.
• An argument for NH to be really involved in the reactions is the fact that deammoniation did not occur when the zeolite was heated at 400° C. after boranation.
• a mordenite sample was prepared in its H-form, dehydrated in a vacuum at 400° C., and reacted with 1.60 mmol B 2 H 6 per g mordenite at 150° C. Then the boranated sample was reacted with NH 3 at room temperature. During this reaction H 2 was evolved, indicating a real reaction between the NH 3 and the BH n groups in the zeolite. When heated at 400° C., again H 2 was evolved and only a small amount of NH 3 was liberated by the zeolite. Deammoniation did not occur and therefore formation of stable B--N bonds in the zeolite is concluded. When treated with water, again a small amount of H 2 was evolved. The sorption properties are measured after each step, and tabulated below.

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• Chemical & Material Sciences (AREA)
• Inorganic Chemistry (AREA)
• Analytical Chemistry (AREA)
• Organic Chemistry (AREA)
• Chemical Kinetics & Catalysis (AREA)
• Solid-Sorbent Or Filter-Aiding Compositions (AREA)
• Silicates, Zeolites, And Molecular Sieves (AREA)

Applications Claiming Priority (2)

Publications (1)

Family

ID=8191004

Family Applications (1)

Country Status (3)

Cited By (3)

Families Citing this family (1)

Citations (13)

• 1983
  • 1983-10-21 EP EP83201516A patent/EP0139788B1/de not_active Expired
  • 1983-10-21 DE DE8383201516T patent/DE3366121D1/de not_active Expired
• 1984
  • 1984-10-18 US US06/662,223 patent/US4620857A/en not_active Expired - Lifetime

Patent Citations (13)

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